Why is there a delay after I tap the "Add" button on iPhone?

On iOS devices, selecting multiple photos or videos can result in a short delay of up to a second per photo, or up to 3 seconds per video after pressing the "Add" button. Unfortunately this is a device constraint specific to iOS.

For context, this happens because an upload to GUESTPIX is the full size, original definition photo or video so that your host gets the best quality possible version of your media. iOS devices sometimes store that media in a "container" called a HEIC file, and it can take a moment for your device to extract the photo or video from this "container".

If you tap 'Add' once, and wait, the device will load in time. Your event host appreciates your patience!